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Old Laptops, Modems, And The Hackaday Retro Edition

We haven’t been getting very many submissions of extremely old computers loading up the Hackaday Retro Edition in a while. For shame. Thankfully, [alnwlsn] is here to pick up the slack from the rest of you with his latest accomplishment, getting two old laptops on the Internet with some old telecom equipment.

The first is a Toshiba from about 1995, Pentium processor, 12 MB of RAM, and a 10 GB (!) hard drive. [aln] had a PCMICA modem sitting around, and with Windows 95 and IE 5.5, he was able to slowly connect.

Pentium class machines are okay, but the next one – a Zenith Data Systems laptop from about 1987 – is awesome. 80C88 CPU, two 720k floppy drives, and the exact amount of RAM in that quote falsely attributed to [Bill Gates]. [alnwlsn] is connecting with a 28.8k modem, but the serial port only supports up to 9600. It’s a computer so old, even the retro edition’s main page times out. The about page, though, loaded fine.

[alnwlsn] used a modem with both of these laptops, but he doesn’t have dial-up or even a landline. This forced him to make his own line simulator that requires plugging in the phone line at the right time, manually ringing a modem connected to another computer, and letting PPP take it from there. It’s a crude circuit, but it works. slow, but it works. Video below.

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Repairing a mill that cost as much as a car

miters

Years ago, someone at the bio-instrumentation lab at MIT needed to change a CMOS battery in the controller for a three axis mill. This reset the machine’s BIOS and was widely regarded as a bad move. The mill sat in the lab for a few years before  Prof. [Ian Hunter] donated it to MITERS – the student shop at MIT. And so the task of repairing a machine that cost as much as a car fell upon a plucky group of students.

The machine – a  Dyna-Myte 1007 has a 10″x7″x10″ work area, pneumatic tool changers and carousel, and the working for a fourth axis. It is. however, driven by an ancient Pentium computer running DOS with all the fun of ISA slots and IRQs that entails.

The MITERS began their repair by digging around in the software configuration, finding the axis drive is controlled via IRQ 3, which was currently occupied by COM 2. Changing that in the BIOS let the computer control the axes and, with a few solenoids and an air compressor, the tool carousel also worked.

With a bit of digging around, the MITERS also got the spindle working, giving them a very awesome and very expensive CNC milling machine for free. Even though the computer could be replaced with a $35 Raspberry Pi, we really have to admire the MITERS for fixing what they already had; it’s a cheaper and much, much faster way to get their new toy up and running.

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